Clean overalls for cleaning and performance testing
1. Clean working clothes
Clean work clothes are special work clothes with dust-free and antistatic properties, which are suitable for electronic, optical instruments, pharmaceutical, microbiological engineering, precision instruments and other industries.
Clean coveralls management is one of the most important link in cleaning, while the fiber itself is difficult to dirty clean fiber, but how to keep is an important factor, that is use the method of cleaning. If the ordinary washing method, of course, on the contrary will be soiled. So you must use a special way. Clean work clothes, from the management into consideration, also when cleaning should be carried out in the clean room cleaning 椄 slightly ACTS the role of packaging.
Usually clean work clothes at least once a week washing, some demanding work even a day washing.
In the ordinary room cleaning, will adhere to dust and bacteria, as well as the contamination of the detergent.
The cleaning of clean work clothes is usually carried out by professional cleaning companies. The matters needing attention in the cleaning process of clean room are as follows:
(1) the newly sewn clean work clothes can be washed directly. If oil is found in the recycled clean work clothes, the oil should be carefully removed before washing.
(2) before washing, the accessories such as scratches, damages and buckles shall be inspected, and the defective ones shall be repaired, replaced or scrapped.
(3) cleaning, drying and packing must be carried out in a clean room with a higher cleanliness than the clean room in the working clothes.
(4) wet and dry cleaning water to be filtered, the solvent to be distilled at the point of use with less than 0.2 m pore size of the filter membrane, as needed for more than one filtration.
(5) in order to remove water-soluble pollutants, wash with water and then use distilled solvents for the final washing to remove oily pollutants.
(6) wet washing water temperature is as follows:
Polyester cloth 60-70 ℃ (maximum 70 ℃)
Nylon fabric 50 to 55 ℃ (maximum 60 ℃)
(7) in the final rinse permeable, antistatic agent can be used to improve the antistatic characteristics, but the selected antistatic agent should be well combined with the fiber, no dust shedding.
(8) work clothes with buckles shall be washed under the buckled state.
(9) dry in the clean air circulation system dedicated for washing.
After drying, dedicated in washing clean indoor fold, into clean polyester or nylon bag inside, according to the requirements can be double packing, also can undertake vacuum encapsulation, had better use the material with good sex of antistatic packaging material. Due to the folding process is the most prone to dust, and folding process must be carried out in higher purification space, such as 100 grade clean coveralls folding packaging should be environment at level 10.
2. Performance test of clean working clothes
2.1 purification performance test
The contamination particles attached to the clothing materials of clean coveralls used in clean rooms are determined by the following four methods :ASTM f-51 method (microscope method), f-51 reduction method (counting method),HELMKE cylinder method (drum method, equivalent to ASTM test method) and vibration test method (vibration method).
(1) astm-f-51 method (microscopic method)
The test probe is equipped with a filter diaphragm, which is directly connected to the suction metering pump, and the air flow is 28L/min. During the test, the air passes through the test fabric, and the dust particles contained in the air are caught onto the filter membrane used in the test, and the number of dust particles is observed and counted with a 400-fold microscope.
Read the number of particles 0.5-5 and above on the filter membrane. Read the number of particles in a cell printed on the filter membrane with a 3.08mm grid.
(2) astm-f-51 revised method (counting method)
The size and number of dust particles are measured by particle counter.
The samples were placed on a platform with a metal mesh, and the sampler (replaced by a 47mm filter holder) was used to contact and attract the samples, and the air flow through it was 28L/min.
(3) Helmke Drum Test
The sample is rotated in a rotating barrel with a side opening, and the dust particles are sampled from the barrel, and the level of cleanliness is determined after the number of particles is measured with a particle counter. The size of the rotating drum is 43cm 33cm, and there are 4 blades on the inside of the barrel, and the revolution of the barrel is 10 revolutions per minute.
The samples were placed in a chamber and subjected to vibration and torsion to produce particles, which were measured with a particle counter.
There is no national standard for testing the dust-free performance of clean work clothes in China, which can be referred to the Japanese industrial standard jis-b-9923 and the American IES standard rp-cc-003-87-t studied by the special committee of Japan air cleaning association.
For the evaluation of dust-free performance, each industry can use it according to the standard of clean workshop stipulated in the international standard ISO/TC209 and their own clean grade.